Liquid cooled muffler with plural expansion chambers



Oct. 18, 1949. F.'.J. CULBERT 2 LIQUID COOL-ED MUFFLER WITH 'PLURAL EXPANSION CHAMBERS Filed May 28, 1947 5 Sheets-Sheet 1 INVENTOR FRED J. CULBERT ATTORNEY F. J- CULBERT Oct. 18, 1949.

LIQUID COOLED MUFFLER WITH PLURAL EXPANSION CHAMBERS Filed May, 2'8, 194? 5 Sheets-Sheet 2 FIG. 3

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Oct. 18, 1949. F. J. CULBERT 2,484,816

LIQUID cooLEn MUFFLER WITH PLURAL EXPANSION CHAMBERS Filed May 28, 1947 5 She'cs-Sheet 3 FRED J CULBERT Oct. 18, 1949. Q F. J. CULBE-RT 9 3 LIQUID COOLED MUFFLER WITH PLURAL EXPANSION CHAMBERS Filed May 28, 19 47 5 Sheets-Sheet 4 Swim/MM FRED .1. CUL BERT Qua/1 F. J. CULBERT 2,484,816

LIQUID COQLED MUFFLER WITH PLURAL EXPANSION CHAMBERS Filed May 28, 1947 I 5 Sheets-Sheet 5 swoon tow FRED J. GULBERT Patented Oct. 18, 1949 LIQUID COOLED MUFFLER WITH PLURAL EXPANSION CHAMBERS Fred J. Culbert, Norfolk, Va.

Application May 28, 1947, Serial No. 751,004

12 Claims. (Cl. 181-52) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) This application is a continuation-in-part of applicants pending application Serial No. 609,298, filed August 6, 1945, now abandoned, for a Muffler.

This invention relates to a water cooled muffler or silencer for the exhaust gases of an internal combustion engine, and particularly, to a muffler for marine Diesel installation.

Numerous types of mufflers or silencers for internal combustion engines are in use. All of these which are of the water cooled type and with which I am familiar have the serious disadvantage of causing an appreciable and in some cases a very objectionable back pressure. Since exhaust back pressure in an engine causes a reduction in hosepower output or an increased fuel consumption per horsepower hour, efforts are constantly made to design exhaust systems with smaller losses of this nature. Furthermore, modern Diesel engine design generally involves a valve lap of as much as 30. That is, there is a short period in the cycle during which both the inlet and exhaust valves are slightly open. During this period it is necessary for the fresh charge of air to enter and scavenge the combustion chamber for eficient operation. But when there is an exhaust back pressure, this might be of sufficient magnitude to prevent any scavenging of the combustion chamber and exhaust gases might enter the air inlet feed. Such a condition prevents efficient operation of the motor.

A commonly used type of water cooled mufller includes a mufiler construction comprising a series of baffle plates over which the exhaust gases must pass in a tortuous path from the inlet to the outlet part of this path being through water. This muffler is fairly satisfactory and is in wide use. However, my experience indicates that this type of muffler, while efficient in reducing exhaust noise at certain engine speeds, introduces into the exhaust system back pressure of sufficient magnitude to cause quite a loss of horsepower. Further, deposits build up rapidly to reduce the efficiency both from the back pressure and the silencing standpoints.

With these defects of the present art mufflers in view, it is an object of this invention to provide an exhaust gas muiil'er which reduces the exhaust noise to a very low level of sound.

It is a further object of this invention to provide a water cooled exhaust gas muflier which develops a very low back pressure during operation.

It is an additional object of this invention to provide a water cooled exhaust gas mufiier which is of relativel light weight and of easily fabricated construction.

It is also a further object of this invention to provide a simplified type of water cooled exhaust muiller of excellent noise reducing capacity together with efiicient cooling of the exhaust gases, all embodied in a mechanically sound and long lasting construction not subject to deposits from the exhaust gases or cooling water.

It is still a further object of this invention to provide a water cooled exhaust gas muffler of relatively short overall length and of sufficient volumetric capacity but capable of fitting into a space restricted longitudinally.

These and other objectives will be apparent from the following description and by reference to the accompanying drawings which are merely illustrative of some of the preferred embodiments of this invention.

In the drawings- Fig. l is a side elevation of my improved muffler with a small portion in section clearly to show the method of construction.

Fig. 2 is a cross section taken along line 2--2 in Fig. 1 looking in the direction indicated by the arrows.

Fig. 3 is an isometric view showing a combination of two inlet chambers with a single exhaust chamber. 1

Fig. 4 is an isometric view showing a combination of one inlet chamber with two exhaust chambers.

Fig. 5 is an isometric view showing an arrangement of a plurality (6) inlet chamber combined with a single exhaust chamber.

Fig. 6 is an isometric view showing a combination of an inlet chamber with an exhaust chamber, the combination being that used in conjunction with a vertical stack exhaust.

Fig. 7 is an isometric view showing a single chamber divided into inlet and exhaust compartments by a slotted partition placed at an angle therein.

Fig. 8 is an isometric view similar to that of 'Fig. 7 but with the slotted partition positioned in the chamber in the median, horizontal, longitudinal plane through the chamber.

Fig. 9 is a transverse section through a combination of an inlet chamber with an exhaust chamber showing a different method of connecting the two chambers together. This construction results in a different positioning of the intercommunicating slot and in a more compact relationship of the two chambers.

Fig. 10 is an isometric view showing the com- 3 bination of an inlet chamber with an intermediate chamber and an outlet chamber all arranged in series relationship.

Fig. 11 is an isometric view showing the combination of an inlet chamber with two intermediate chambers and an outlet chamber.

Fig. 12 is an isometric view showing the combination of two inlet chambers with an intermediate chamber and an outlet chamber.

Fig. 13 is an isometric view showing the combination of two inlet chambers with two intermediate chambers and a single outlet chamber.

Fig. 14 is an isometric view showing the combination of two inlet chambers with a single intermediate chamber and two outlet chambers.

In the embodiment of th invention as shown by Figs. 1 and 2 the muffler comprises two cylindrical chambers l and 2 secured together approximately tangentially throughout their lengths with a communicating slot 3 from one to the other. Opposite end walls 4 and 5 of the two cylindrical portions are angularly disposed for the elimination of hot pockets of gas which were found to exist in the mufllers first constructed with these end walls at right angles to the longitudinal center line of the chambers. 'The chamber I, at the end opposite wall 4 is closed and provided with an inlet opening 6. Chamber 2 is provided with an outlet opening 8 opposite end wall 5. In the upper portion of chamber I and located near inlet 6 is a cooling Water inlet 1. Disposed beneath this inlet 1 and above inlet 6 is a deflecting plate 9 extending from side to side of chamber l and serving to spread incoming water for eflicient mixture with the hot incoming exhaust gases. This deflecting plate 9 also prevents the cooling Water from back flow into the inlet line. At the outlet end of the lower chamber 2 is shown a plugged drain l which may be located Wherever desired in the low area of the system.

Installation of the mufiler as described includes connecting inlet 6 directly or as desired with the exhaust manifold of the engine. Exhaust outlet 8 will be extended by suitable means to the desired place of disposal of the gas and water mixture, generally by means of a tail pipe provided with a trap or a vertically compound curve to seal the interior of the muffler from the outside atmosphere. The temperature of the exhaust gas and water mixture leaving the mufiier is relatively low (of the order of 130 F.) and may in some cases be conducted from the exhaust chamber by means of a flexible pipe or armored hose in which case the exhaust outlet 8 may not be flanged as shown by Fig. 1. Also the inlet opening 6 may not be flanged as shown. Inlet 1 will be connected to some suitable source of water supply.

Figs. 3, 4 and show structural modifications of the simple combination of one inlet chamber with one exhaust chamber. The reason for these variations is that in replacing an existing muiller on board a ship space may not be available longitudinally for the installation of a mufller of sumcient volumetric capacity. The required volume may be obtained by increasing the number of inlet chambers, by increasing the number of exhaust chambers or by increasin the number of both and at the same time reducing the overall length of the assembly.

Fig. 6 discloses a modification of the type of mufiier shown by Figs. 1 and 2 which is adapted for exhaust into a vertical stack. In this modification the exhaust gas inlet is into the lower chamber and the outlet is from the upper chamber. The water inlet is into the upper chamber and the outlet thereof is from the lower chamber which is frusto conical in shape to provide proper water drainage.

Figs. 7 and 8 disclose a single chamber divided into inlet and exhaust compartments by a slotted partition plate which is placed in the chamber obliquely in Fig. 7 and medially longitudinally of the chamber in Fig. 8. The underlying reason for these modifications may again be the dimensions of the space available on board a ship.

Fig. 9, as above stated, shows a more compact construction of the muffler. Here both the inlet and the outlet chambers are slotted out longitudinally to provide a radial overlapping of the two chambers. The intercommunicating slot between the two chambers is in this overlapped portion.

Figs. 10 to 14 are merely illustrative of several combinations of inlet, intermediate, and outlet chambers. They should not be understood as limiting the invention to these particular combinations since many other combinations are possible and are within the scope of the invention as described and claimed herein.

In operation, exhaust gases pass through inlet 6, through a curtain of water supplied through inlet 1 and descending from the edge of deflecting plate 9. Observation of a specifically constructed transparent model of the muiller shows that the gases travel in an S-curve through the device while the water not entrained flows down the side walls of the upper chamber. Gases and water pass through the slot or openings 3, Whereupon much of the water flows down the side walls of chamber 2. Entrained water carried with the gases impinges upon end walls 4 and 5. Mixing of the gases with the water is very thorough leading to a considerable evaporation of the water and probably some solution of the gas in the water both of which produce an eflicient cooling of the gas and a large reduction of gas volume. This reduction in gas volume accounts for the low back pressure developed by this muffler. All Walls of the device are cooled so thoroughly that no lagging or other type of insulation is required. Water, vapor, and gas are thoroughly intermingled in the tail pipe leading from outlet 8. While they appear to be moving rapidly and under high pressure, tests indicate a pressure rise through the system so low as to be measured with diificulty.

The reduction of the noise level by this mufiler is remarkable. Various theories have been advanced as to how this mulliing action is accomplished. The most reasonable one is that the Water in flowing down the side walls of both chambers produces a moving wall from the surface of which the sound waves are diffusely reflected. In other words the sound is scattered and the result is a reduction in noise volume. The mufiler is particularly quiet in installations where the tail pipe has a water seal in it so that there is no direct communication over the surface of the water in the tail pipe between the outside air and the interior of the mufiier. Sound tests indicate a mufiling efficiency at least equal to present art mufllers which cause a considerably higher exhaust back pressure.

In most installations outlet 8 is so situated as to allow a quantity of water to remain in the bottom of chamber 2. In operation, this water is continuously changed, but when the engine is not running it remains in the mufiier. Drain plug II] is for the purpose of occasional inspection and clean out if necessary. Operation of several installations over a period of months indicates that the action of the gases and water inside the mufiler are such as to result in substantially no solid deposits, whether from the exhaust gases in the form of carbon or from solids contained in the water supply.

As described, the entire mufller is a weldment totally fabricated from easily procurable standard stock by common welding procedures. In fact, due to the low internal pressures existing in the muffler it may be fabricated from sheet stock thus effecting a.relatively large saving in weight. The construction is sturdy and economical. It has been found that due to the simply formed interior, treatment such as hot-dip galvanizing or vitreous enameling of the completed device is practicable.

While disclosed as particularly suited to marine use, the muffler may be used in any service where cooling water is available.

The invention described herein may be made or used by or for the Government of the United States of America for governmental purposes Without the payment to me of any royalties thereon or therefor.

What is claimed is:

l. A water cooled mufiier for the exhaust gases of an internal combustion engine comprising an assemblage of elongated chambers juxtapositioned with exterior walls of adjacent chambers in contact with each other, certain of said cylinders being vertically disposed with respect to others of said chambers, the said assemblage including at least one gas inlet chamber, at least one gas outlet chamber, at least one gas inlet in each inlet chamber, at least one water inlet in each inlet chamber, a deflecting plate secured in each inlet chamber below each water inlet and above each gas inlet for spreading the incoming water in a sheet transverse to the flow of the incoming gas, at least one exhaust outlet in each outlet chamber and walled conduit means for communication between said chambers.

2. A water cooled muffler for the exhaust gases of an internal combustion engine comprising two elongated chambers juxtapositioned with the external walls of adjacent chambers in contact with each other one above the other with a walled communication between the chambers of a longitudinal, horizontal area small relative to the transverse sectional area of the chambers, one chamber being the gas inlet chamber and the other the gas outlet chamber, a gas inlet in one end of the inlet chamber, a gas outlet in the opposite end of the outlet chamber, a water inlet close to and above the gas inlet of the gas inlet chamber and a deflecting plate positioned in the gas inlet chamber above the gas inlet, and below the water inlet for spreading the incoming Water in a sheet transverse to the fiow of the incoming 3. A water and gas impinging type of exhaust mufller for use in connection with internal combustion engines comprising at least two chambers juxtapositioned with external Walls of adjacent chambers in contact with each other one above the other, an upper chamber having an oblique closure at one end, an exhaust gas inlet in the opposite end of the upper chamber connected to the exhaust manifold of an internal combustion engine, a water inlet in the side wall of the upper chamber positioned above the exhaust gas inlet, a deflecting plate positioned in the upper chamber below the Water inlet and above the exhaust gas inlet for spreading the incoming water and causing it to flow over the walls of said chambers, an oblique closure at one end of the lower chamber, an exhaust gas outlet in the opposite end of the lower chamber connected to a discharge pipe to permit the discharge of the combined gases and water and a relatively narrow slotted passageway between said chambers for gas and water flow therebetween.

4. A muffler as defined in claim 3 in which the said chambers are circular in cross section.

5. A water cooled mufiier as defined in claim 1 in which the said assemblage comprises two separate gas inlet chambers and one exhaust chamber, both inlet chambers connected to and separately communicating with the exhaust chamber.

6. In a water-cooled mufiler for the exhaust gases of an internal combustion engine, a plurality of substantially cylindrical chambers juxtapositioned with the exterior walls of adjacent chambers in contact with each other and having their longitudinal axes substantially horizontal, certain of said chambers being vertically disposed with respect to others of said chambers, longitudinal restricted passages connecting adjacent vertically disposed chambers, a water inlet in at least one of the uppermost of said chambers, a deflecting plate situated within said chamber adjacent said water inlet to spread the water over a large portion of the surface of said uppermost chamber, the water flowing over and substantially covering the walls of successive vertically disposed chambers, exhaust gas inlet means attached to at least one of said chambers, and means for exhausting the cooled exhaust gases from a chamber other than that containing said exhaust gas inlet means, said water exhausting through an opening in the lowermost chamber.

7. In a water-cooled muffler for use in connection with internal combustion engines comprising, a plurality of substantially cylindrical expansion chambers juxtapositioned with the exterior walls of adjacent chambers in contact with each other and having their longitudinal axes substantially horizontal, certain of said chambers being vertically disposed with respect to others of said chambers, adjacent vertically disposed expansion chambers being connected together by longitudinal restricted passages, water inlet means in the top portion of the uppermost of said vertically disposed chambers, water deflecting means secured adjacent said water inlet means to spread the water over substantially the entire wall surface of the uppermost of said chambers, whereby the water flows over and substantially covers the wall surface of successive vertically disposed chambers, exhaust gas inlet means near one vertical extremity of said vertically disposed chambers, and outlet means for the cooled exhaust gases near the other vertical extremity of said vertically disposed chambers, said water exhausting through at least one opening in the lowermost chambers.

8. In a water-cooled muffler for use in connection with internal combustion engines, a plurality of substantially horizontal expansion chambers juxtapositioned with exterior walls of adjacent chambers in contact with each other and comprising a pair of inlet chambers each having an exhaust gas inlet, a water inlet disposed in the top of each of said inlet chambers, a water deflecting plate disposed in each of said inlet chambers adjacent to each of said water inlets to spread the water over the wall surface of said inlet chambers, an intermediate chamber disposed below and in contact with each of said input chambers and connected therewith by longitudinal restricted passages, an outlet chamber having exhaust gas outlet means attached thereto disposed below and in contact with said intermediate chamber and connected with said intermediate cylinders by means of longitudinal restricted passages, whereby the water covers the wall surface of said chambers by gravitation from said input cylinders and exhausts through said exhaust gas outlet means.

9. A water-cooled muffler for use in connection with internal combustion engines comprising, a plurality of cylindrical expansion chambers juxtapositioned with exterior walls of adjacent cylinders in contact with each other and having their longitudinal axes substantially horizontal, an inlet chamber having an exhaust gas inlet, a water inlet in the upper portion of said inlet chamber, a water deflecting plate positioned below said water inlet and above said exhaust gas inlet to spread said water over the wall surface of said inlet chamber, an intermediate chamber positioned below and connected with said input cylinder by a longitudinal restricted passage, an outlet chamber situated below said intermediate chamber and connected therewith by a restricted longitudinal passage, whereby the walls of said intermediate and outlet chambers are covered with water gravitating from said inlet chamber, and means for exhausting said water and said exhaust gases from said outlet chamber.

10. In a water-cooled mufiler for use in connection with internal combustion engines, a plurality of horizontal cylindrical chambers juxtapositioned with external walls of adjacent chambers in contact with each other and comprising an inlet chamber having an exhaust gas inlet, a. water inlet in the upper wall of said inlet chamher, a deflecting plate positioned within said chamber below the water inlet and above the exhaust gas inlet to spread the water over the inlet chamber Wall, means including a longitudinal slot connecting said inlet chamber to a second vertically disposed cylindrical chamber disposed below said inlet chamber, and means for exhausting said water and exhaust gases from said second chamber.

11. In a water-cooled mulfler for use with internal combustion engines, a group of substantially horizontal expansion chambers juxtapositioned with external walls of adjacent chambers in contact with each other, certain of said chambers being vertically disposed with respect to others of said chambers, restricted longitudinal passages connecting adjacent vertically disposed chambers, water inlet means in the upper portion of said group of vertically disposed chambers, water deflecting means positioned adjacent said water inlet means to distribute water over the walls of said upper portion of said chambers, and water exhaust means attached to the lowermost portion of said group of vertically disposed chambers whereby the walls of said vertically disposed chambers are substantially covered with water gravitating from said upper portion of said group of chambers, exhaust gas inlet means connected to said bottom portion of said group of vertically disposed chambers, and exhaust gas outlet means connected to said upper portion of said group of chambers, whereby said exhaust gases are cooled by contact with the Water covering the walls of said chambers.

12. In a water-cooled muffler for use with internal combustion engines, a cylindrical outlet chamber having its longitudinal axis substantially horizontal, a water inlet in upper side wall of said outlet chamber, a water deflecting plate positioned within said outlet chamber adjacent said water inlet to spread said water over the walls of said outlet chamber, a frusto conically shaped inlet chamber below and in contact with said outlet chamber, a longitudinal restricted passage connecting said chambers, water outlet means attached to the low end of said inlet chamher, and an exhaust gas outlet attached to said outlet chamber.

FRED J. CULBERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 940,290 Tobey Nov. 16, 1909 965,090 Dlouhy July 19, 1910 1,065,707 Montgomery June 24, 1913 1,120,387 Hutchins Dec. 8, 1914 2,124,489 Hurlock July 19, 1938 

